Technical Field
The present invention relates to 3D (three-dimensional) graphics processing, and in particular, it relates to methods and apparatuses for computing trigonometric functions with high precision.
Description of the Related Art
Trigonometric functions are included in all 3D (three-dimensional) graphics APIs (Application Programming Interfaces), such as DirectX and OpenGL. In order to satisfy the performance requirements of 3D graphics under certain constraints, GPUs (Graphics Processing Units) take specific hardware logic units called SFUs (Special Function Units) to compute trigonometric functions and other transcendental functions. 3D graphics API only require the maximum absolute error being 0.0008 in the interval from −100*Pi to +100*Pi for trigonometric functions, which can be achieved by SFUs. However, the traditional SFU computing methods cannot meet higher precision requirements of GPGPU (General-Purpose computing on Graphics Processing Unit) for trigonometry functions. Thus, methods and apparatuses for computing trigonometric functions are introduced to achieve the precision requirements of GPGPU.